. >> reporter: the los angeles county sheriff's department teaches staff the best way to use social media to solve crime. >> you can go back to those creative writing classes with the understanding that you have potential civil and criminal consequences for what you write. >> reporter: they warned writers not to use racially charged language and must never post rumors. the instructor teaches the good relations with the citizens. >> you have to speak to them when there is not an emergency in order to buildi a following o when the crisis happens, that you're there and you're able to help them, and they know where to find you. >> reporter: through social media, police gain the potential help of thousands of citizens, and as relgtss between the police and public improve, criminals have less room to maneuver. mayumi maruyama, nhk world, los angeles. >>> japan's nuclear regulation authority is considering investigating potentially active faults near nuclear plant under construction in northern japan. chairman tanaka said any doubts about false nuclear plans must be cleared up. he said the autho